The hepatitis B virus (HBV) causes liver disease that can range in severity from a mild illness that lasts several weeks (acute hepatitis B) to a long-term chronic illness. An estimated 2 billion people have been infected with HBV worldwide, resulting in more than 350 million individuals with chronic, long-term liver infections. Patients with chronic HBV infection are at a great risk for the development of cirrhosis, hepatic failure, and HCC. There is no cure for hepatitis B and care is mostly palliative. There are several anti-viral and interferon drugs, such as Entecavir and Interferon α therapy, which can help some patients. However, these drugs are costly, thousands of dollars per year, and are not widely available in many countries, especially in the developing world. Vaccination is available and effective and is recommended for all individuals at risk for HBV infection. However, vaccination is only effective in individuals who have not been exposed to HBV. Hepatitis B is closely linked to liver cancer, which is almost always fatal.